EW SYSTEM 



ASTRONOM Y, 



QUESTION AND ANSWER. 



FOR THE USE C< 

SCHOOLS ANI> ACADEMIES 







i 

4 i 
i 




BY ALVA CLARK, A. 3. 




NEW YORK 1 

ROE LOCJKWOOD & c ON, 

SCHOOL BOOK DEPOSITORY, 411 BROADWAY 




Class Q B 4i>_ 
Book £jb 



A 

NEW SYSTEM 



ASTRONOMY, 

m 

QUESTION AND ANSWER. 

FOR THE USE OP 

SCHOOLS AND ACADEMIE& 



BY ALYA CLARK, A.B. 



N*to Yorft: 

R. LOCKWOOD, 411 BROADWAY. 

S. W. Benedict, Printer , 

1843. 






SOUTHERN DISTRICT OF NEW YORK, ss. 

BE IT REMEMBERED, that on the 8th day of March, in the I rty-fourth year of the Ii__^_ 
c» .he United Stito of America, Alvah Clark, of the said District, has deposited in this office tlw title u. i 
Book, the right whereof t> Ociai Amrjor and Proprietor, in ti* words following, to wit: 

• A New System of Astronomy, in Question and Answer, for the Use of Schools and Aciutemie*. By 
Aj van Clark, A.B." 

(n confonnity '.o the act of Congress of the United States, entitled, " An Ad fcr the encouragement o( 
Leu: 'ug, ly «curing the copies of Maps, Charts, and Books, to the authors and proprietors of suiJi 
cop»«, during the times tlierein mentioned." And also to an Act, entitled, " An Act, supplementary to an 
Art, autiUed an Act for the encouragement of Learning, by securing the copies U Maps, Charts, rut 






PREFACE. 



The following system of Astronomy was written some time since, 
for the use of those by whom I was employed as private instructer, 
and for the use of Miss Desabye's Boarding School, in which I am en- 
gaged to superintend the English department. Knowing, therefore, 
from experience, that their acquisition of the knowledge of the elements 
of Astronomy has been facilitated by this work, more than by any 
other which I could place before them, I am induced to publish it, be- 
lieving that, while it relieved me from the laborious duty of copying it 
for every student, it would serve to introduce into our Schools and 
Academies, the study of this useful and important science. 

The study of Astronomy has been too much neglected in the system 
of education. This has probably arisen from the want of some astro- 
nomical work, which could be introduced into schools at a small expense 
and which would render this science intelligible tc youth. These ob- 
jects, it is believed, will be effected by the following work, which is now 
published for the use of those who find it necessary to complete their 
education at Schools and Academies without enjoying the advantages 
of a liberal education at college, where the science of Astronomy 
would be embraced in their course of studies. 

When I have conversed with teachers on the propriety of making 
Astronomy a branch of elementary education, they have observed that 
the usual works on that science were too expensive, and were like- 
wise accompanied by many geometrical and algebraical explanations, 
which the young student could not comprehend, and of which a know- 
ledge could not be acquired in the short period allotted to elementary 
education. This objection, supported by fact, has influenced me to 
avoid, in the definitions and explanations, too frequent use of technical 
terms, and to omit some things which are not practically useful, and 
can be understood by those only who are acquainted with the higher 
branches of geometry and mathematics. 

To obtain an accurate knowledge of the following work, it will be 
necessary for the teacher to require the student to explain, as far as 
possible, every definition and problem upon the globes. No impres- 
sions are so clear and impressive as those presented to the eye. The 
reasons for this I need not now enumerate. Experience, the infallible 
test of every theory, fully confirms this assertion. 

Though the general importance and utility of the study of Astrono- 
my has never been denied, yet I have often heard it observed, that it is 
entirely useless in the system of female education. All the reasons 
which can be given in support of this position are equally forcible 
against the benefit of any science to the female mind. The science of 
Astronomy explains and illustrates the phenomena of the natural 
World, and exhibits, in the system of the universe, that harmony and 



order, which bespeak the creative power and wisdom cf the Deity. It 
enlarges the faculties, and strengthens the energies of the mind. If 
such a study must be rejected from the system of female education^ 
•where, I ask, will retrenchment end ? 

> If the objection arise from the opinion, that the female mind is not 
competent to the investigation cf the Elements of Astronomy, I leave 
it to the contempt 't so justly deserves, only asking the objector on 
what authority he attributes to the female sex, that inferiority of intel- 
lect which his objection supposeo ? 

I have for some time past, been exclusively engaged in the business 
of instruction : and my own experience, and the opinion of those 
teachers in whom I place the highest confidence, have convinced me, 
that the method of instruction by "question and answer," is, in many 
branches of education, highly beneficial ; provided the questions are so 
constructed, that the answers to them will necessarily involve all the 
important principles of the science to which they are adapted. 

When the lesson in this form is placed before students, they know 
what will be required of them in the recitation, and are sure that no- 
thing, which will be required, has escaped their attention. Such a 
course of study inspires them with confidence, and dissipates that un- 
certainty, which perplexes and confuses the mind, and destroys all 
that pleasure which is to be derived from the pursuit of literature. 

These views have influenced me to adopt, as far as possible, the 
catechetical mode of instruction. I shall be cautious not to carry it too 
far; but to adopt it to that extent, which, while it diminishes the 
labour of the teacher, will promote the assiduity, advancement, and 
satisfaction of the student. 

That teachers and the public concur with me in this respect, I have 
sufficient evidence, in the unexpected and rapid sale of a work which I 
lately published, entitled, "Questions adapted to the study of Tytler's 
Elements of History." And in the approbation given to a similar work, 
entitled, "Questions to Blair's Rhetoric," published by A. Bixby, prin- 
cipal of John-street School. 

Should the encouragement given to those works he extended to this, 
I shall publish some others, calculated to introduce into the schools of 
this country, some salutary branches of literature, which have been 
hitherto excluded from the attention of youth either by extending the 
volumes which contain them, to an unnecessary expense, or by treat- 
ing of them in a manner not suited to the general use of schools and 
academies. 

I confidently trust, that the experience of other teachers will con- 
vince them of the utility of this method of instruction ; since it is one. 
which makes their own duties less laborious, and consults the welfare 
of students, by making them confident of their ability to acquire a 
knowledge of those sciences, whose obscurity, or difficulty, has hither- 
to checked their progress, and discouraged their application. 

tScu- Yoik, March 1WA, 1620. 



ASTRONOMY. 



FART I. 



SECTION I. 

Definitions. 

'What is Astronomy ? 

It is the science which treats of the heavenly 
bodies. 

What do we learn by it 7 

We learn the figure, dimensions, motion, and rela- 
tive distances of the heavenly bodies. 

What is an Angle 7 

It is the space contained between two lines meeting 
at a point. 

What is a Right Angle ? 

It is an angle formed by one line 
falling perpendicularly upon another, 
thus : 

A B C is a right angle, or contains^, 
ninety .degrees. 



What is an Acute Angle ? 

It is less than a right angle, or 
contains less than ninety de- 
grees. JK 

What is an Obtuse An- 
gle? & 

It is greater than a right 
angle, or contains more than 
ninety degrees. 

1" 





"iT 



A is a figure bounded by three 




What is a Triangle 7 
Iti 
rides. 

bZ ^e 

What are Parallel Lines 7 

Those which never approach — — 

each other. — — — 

What is a Circle 7 

It is a plain figure bounded by a curve line, every 
part of which is equally distant from a point called the 
centre. 




1. The Circumference is the curve line that bounds 

2. The Radius is a straight line drawn from the 
centre to the circumference, as AC or CB — all radii 
are equal. 

3. The Diameter is a line drawn through tlie 
centre, terminated both ways by the circumference, 
as AB. 

4. An Arc is any part of the circumference, as 
DF. 

5. The circumference is divided into 360 degrees ; 
each degree into 60 minutes, and each minute into 60 
seconds. 



What is a Sphere 7 

A sphere is properly a globe ; but in Astronomy, 
tAe celestial sphere means the apparently concave orb 
of the heavens, in which all the heavenly bodies ap- 
pear to be placed. 

What is the Axis of a heavenly body ? 

It is an imaginary line, round which it performs its 
daily motion. 

To what is it equal ? 

It is equal to a diameter. 

What is the Axis of the Artificial Globe 7 

It is a line which passes through its centre from one 
pole to the other. 

What are the Poles of a Great Circle 7 

They are two points equally distant from every part 
of its circumference. 

What are the Poles of the Earth 7 

They are the extremities of the axis; and are called 
the north or arctic pole, and the south or antarctic 
pole. 

What are the Celestial Poles 7 

They are the extremities of the earth's axis produ- 
ced to the heavens. 

What is the Diameter of a sphere ? 

It is a straight line which passes through the centre, 
and is terminated both ways by the surface of the 
sphere. 

What is the Circumference of the sphere ? 

It is any great circle drawn on its surface. . 4 

How are the circles of the sphere divided 1 v \ 

In two kinds — Great and Small. 

What is a Great Circle 7 

It is that whose plane divides the sphere into two 
?qual parts, called hemispheres. 

What is a Hemisphere 7 

It is half a globe. 

How many hemispheres are there ? 

The number is innnite 5 as any great circle divide? 



8 

the g>obe into two hemispheres. Those most fre- 
quently used are six : 

1. The Northern and Southern, formed by the equa- 
tor. 

2. Tne Eastern and Western, formed by ameridian. 

3. The Upper and Lower, formed by the rational 
horizon. 

Mention the principal great circles. 

There are four : Equator, Ecliptic, Meridian, and 
Horizon. 

Can two great circles be parallel ? No. 

What is a S?nall Circle ? 

It is that whose plane divides the globe into two 
unequal parts. 

Mention the principal small circles. 

They are four : the two Tropics and two Polar 
Circles. 

What are the Parallels of Latitude 

They are all those small circles parallel to the equa- 
tor. 

Are all small circles parallel to the equator ? 

They may be parallel to the ecliptic, horizon, me- 
ridian, or any other great circle. 

What are parallels of latitude on the celestial 
globe? 

They are small circles parallel to the ecliptic ? 

What are Parallels of Declination ? 

They are small circles parallel to the equator, and 
are the same as parallels of latitude on the earth. 

What are Parallels of Altitude ? 

They are small circles parallel to the horizon. 

What are Concentric Circles ? 

They are circles drawn round the t 
same centre. 

What are Cardinal Points 7 

They are certain fixed points that , 
never change, and to which all calcu- 
lations are referred. 




SECTION II. 

Of the Equator. 

What is the Equator 7 

It is a great circle whose plane divides the earth 
into northern and southern hemispheres. 
How far distant is it from the poles 7 
Every part of it is ninety degrees distant. 
What is it called when referred to the heavens ? 
The Equinoctial. 
What is it called by mariners 7 
The Line. 

What are reckoned on it 7 
Longitude, right ascension, &c. 



SECTION III. 

Of the Meridian, 

What are Meridians 7 

They are great circles, whose planes divide the 
globe into eastern and western hemispheres. 

What is their direction 7 

They all pass through the poles, and cut the equator 
at right angles. 

How many meridians are there 7 

Their number is unlimited ; there may be as many 
as there can be taken points on the equator 

Why are they called Hour Circles 7 

Because as they are drawn on most globes, the sun 
masses from one to another of them every hour 7 

What supplies their places as hour circles 7 

The hour circle and its index. 

What is the Hour Circle 7 

It is a small circle of brass fixed to the north pole, 
vith the hours of the day marked on it. 

What is the First Meridian 7 



10 

It is that from which geographers begin to count 
the longitude. 

What first meridian is most frequently used 7 

The meridian of London. 

What is the Brazen Meridian ? 

It is that in which the artificial globe turns. 

How are the degrees numbered on it ? 

On the upper semicircle from the equator towards 
the poles — on the lower semicircle from the poles 
to the equator. 

What is Longitude ? 

It is distance east or west from the first meridian 
reckoned on the equator. 

What is the greatest longitude a place can have ? 

One hundred and eighty degrees either east or west 
from the meridian. 

What is Latitude ? 

It is distance either north or south from the equator, 
reckoned on a meridian. 

What is the Greatest Latitude a place can have ? 

Ninety degrees either way from the equator. 

What is Declination, on the celestial globe ? 

It is the distance north or south from the equinoctial, 
and corresponds to latitude on the earth. 

How is latitude reckoned on the celestial globe ? 

Ninety degrees each way from the ecliptic. 

What is longitude in the heavens ? 

It is distance on the ecliptic, reckoned eastward 
from the first degree of the sign Aries. 

What is the greatest longitude of a heavenly body ? 

Three hundred and sixty degrees, beginning at the 
first degree of Aries, and reckoning on the ecliptic 
eastward quite round the globe. 

What is the greatest latitude of the sun, a planet 
and star. 

1. The sun being always in the ecliptic, has no 
latitude. 



11 

2. A planet can have only eight degrees of latitude, 
because it never leaves the zodiac^ which is eight 
degrees wide on each side of the ecliptic* 

3. A star may have ninety degrees of latitude. 
What is the greatest declination of the sun, a planet, 

or star? 

1. The greatest declination of the sun is about 
twenty-three degrees and a half. 

2. That of a planet about thirty-one degrees and a 
half to the limit of the zodiac. 

3. That of a star 90 degrees. 

What are the Geocentric latitudes and longitudes of 
the planets ? 

Their latitudes and longitudes as seen from the 
earth. 

What are their Heliocentric latitudes and longi- 
tudes ? 

Their latitudes and longitudes as seen from the sun. 

What is the Rigid Ascension of a heavenly body? 

It is that degree of the equinoctial, which rises 
with the body in a right sphere ; and is reckoned 
from the first degree of Aries eastward round the 
globe. 

What is Oblique Ascension 7 

It is that degree of the equinoctial, which rises with 
the body in an oblique sphere, and is reckoned in the 
same way. 

What is Oblique Descension ? 

It is that degree of the equinoctial which sets with 
the body in an oblique sphere. . 

How many positions has the sphere ? 

Three ; Right, Oblique, and Parallel. 

What is a Right Sphere ? 

It is that in which all the circles of daily motion lise 
directly above and descend directly below the horizon. 

How is it represented ? 

By placing both poles in the horizon 



12 

What is an Oblique Sphere ? 

It is that in which all the circles of daily motion are 
Oblique to the horizon. 

How is it represented 1 

By raising one pole a little, and depressing the other. 

What is a Parallel Sphere ? 

It is that in which the equator coincides with the 
horizon, and all the circles of daily motion are parallel 
to the horizon. 

How is it represented 1 

By elevating one pole to the zenith, and depressing 
the other to the nadir. 

What places have each of these spheres ? 

Those directly under the equator have a right 
sphere, those between the equator and poles have an 
oblique sphere, and those directly under the poles have 
a parallel sphere. 



SECTION IV. 

Of the Ecliptic 

What is the Ecliptic 7 

It is a great circle which intersects the equinoctial 
at an angle of about twenty-three degrees and a half. 

Of what is it the path ? 

It is the orbit in which the earth revolves round the 
sun once a 3rear. 

What are the Equinoctial Points ? 

They are the points where the ecliptic and equmoc- 
lial intersect each other. 

When does the sun pass these points 

It passes Aries twenty.-first of March, called the 



13 

vernal equinox, and Libra twenty-third of September, 
called the autumnal equinox. 

"When are the day and night every where equal ? 

When the sun is in the equinoxes. 

What are the Solstitial Points ? 

They are the points of the ecliptic farthest from the 
equinoctial, or where it touches the tropics. 

How far from the equinoctial to the solstitial points ? 

Ninety degrees, or a quarter of a circle. 

When is the sun in the solstitial points ? 

On the twenty-first of June, called the summer sol- 
stice, and on the twenty-second of December, called 
the winter solstice. 

What are their signs ? 

Cancer is the northern or summer solstice. 

Capricorn the southern or winter solstice. 

What is said of the day and night when the sun is 
in these signs ? 

1. When the sun enters Cancer, all places in the 
northern hemisphere have their longest day. and those 
in the southern their shortest day. 

2. When the sun enters Capricorn, all places in the 
southern hemisphere have their longest day, and those 
in the northern their shortest day. 

3. When the sun enters Cancer, all places within 
the north polar circle have constant day, and all places 
within the southern constant night. 

4. When the sun enters Capricorn, all places within 
the south polar circle have constant day, and all those 
within the northern constant night. The last two ap- 
pearances continue for a short time only ; but it is to 
be observed, 

5. That some places within the south polar circle, 
have continual night during the whole six months the 
sun is north of the equinoctial, and some places within 
the north polar circle have at the same time perpetual 
day ; and. 



14 

6. That during the six months the sun is south of 
the equinoctial, some places within the south polar 
circle have continual day, and some within the northern 
continual night. 

NOTE. These six statements may be explained upon the globe. (See part 3, 
Problem 18.) 

What is the Equinoctial Colure ? 

It is that meridian which passes through the equi- 
noctial points. 

What is the Solstitial Colure 7 

It is that meridian Which passes through the solsti- 
tial points. 

How is the ecliptic divided ? 

Into Twelve Signs, each containing thirty-degrees. 

Mention the names of the signs, and the day on 
which the sun enters them. 

T Aries twenty-first of March. ) 

b Taurus twentieth of April. \ Spring signs. 

H Gemini twenty-first of May. \ 

52 Cancer twenty-first of June. ) 

SI Leo twenty-third of July. \ Summer signs. 

i£ Virgo twenty-third of August. \ 

«2= Libra twenty-third of Sept. ) 

m Scorpio twenty-third of Oct. \ Autumnal signs. 

J Sagittarius twenty-third Nov. ) 

V3 Capricornus twenty-second Dec. ) 

'- Aquarius twentieth January. V Winter signs. 

H Pisces eighteenth February. ) 

What are the cardinal points of the ecliptic '? 

They are the equinoctial and solstitial points. 

What is the Zodiac ? 

It is a space sixteen degrees wide, extending eight 
degrees on each side of the ecliptic : and contains tba 
orbits of the planets. 

What is the Orbit of a planet } 

It is the path in which it revolves round the sun. 

What is the Figure of these orbits? 

Elliptical, or longer one way than the other. 



15 

How do the planets revolve in them ? 

From west to east round the sun. 

What are the Apparent Motions of the planets ? 

Three ; Direct, Stationary, and Retrograde. 

1. A planet's motion is said to be Direct, when to a 
spectator on the earth, it appears to move forward in 
its orbit from west to east. 

2. It is said to be Stationary, when it appears for 
some time in the same point of the heavens. 

3. It is said to be Retrograde, when it appears to 
move backward in its orbit, from east to west, con- 
trary to the order of the signs. 

What are the Nodes 7 

They are the two opposite points, where the orbit 
of the planet intersects the ecliptic. 

What is Aspect 7 

Aspect of the stars or planets is their situation and 
relative distances with respect to the sun and each 
other. 

What is the Aphelion 7 

It is that point of the orbit farthest from the sun. 

What is Perihelion 7 

It is that point of the orbit nearest the sun. 

What is Elongation. 7 

[t is the apparent distance of any body from the 
sun. 

What is Apogee 7 

It is that point in the orbit of the moon or any planet 
farthest from the earth. 

What is Perigee7 

It is that point in the orbit of the moon or planet 
nearest the earth. 

The Apsis Line is that which joins the aphelion and 
perihelion, or which joins the apogee and perigee. 
These definitions are thus explained : 



16 

Let S be the Sun 
mid C the centre of 
the orbit; then A, 
the point nearest 
the Sun, is the peri- 
helion ; and B, the 
point farthest from 
the sun, is the aphe- 
lion. As the sun is 
not exactly in the 
centre of the orbit, 
the distance from C, the centre of the orbit, to the 
centre of the sun, is called the Eccentricity 

How do the planets move in their orbits ? 

Variably ; sometimes faster and sometimes slower. 

What is the Mean place of a planet 1 

It is the place where it would be if it moved in its 
orbit with equal velocity at all times. 

What is the True place ? 

It is the place where it really is. 




section v. 



Of the Horizon. 

What is the Horizon 7 

It is the circle which separates the visible part of the 
Heavens from the invisible. 

How many horizons are there ? 

Two ; Sensible and Rational. 

What is the Sensible Horizon ? 

The sensible or apparent Horizon is that circle 
vhich bounds our prospect where the earth and sky 
appear to meet. 

What is the Rational Horizon ? 

It is a great circle whose plane is parallel to the 



17 

plane of the visible horizon, and divides the earth into 
upper and lower hemispheres. 

What is the Wooden Horizon 7 

It is that circular plane circumscribing the artificial 
globe, which represents the rational horizon. 

What are the cardinal points of the horizon ? 

They are east, west, north, and south. 

What are the cardinal points in the heavens ? 

The Zenith and Nadir. 

What are the Poles of the horizon ? 

The Zenith and Nadir. 

What is the Zenith I 

It is the point in the heavens exactly over our 
heads. 

What is the Nadir 7 

It is the point in the heavens opposite to the zenith, 
or directly under our feet. 

What is the Mariner's Compass 7 

It is a representation of the horizon, and is divided 
into 32 equal parts. 

What is the variation of the compass 7 

It is the deviation of the north and south points of 
the magnetic needle, from the north and south points 
of the horizon, either east or west. 

What is an Azimuth or Vertical Circle 7 

It is a circle passing through the zenith and nadir, 
cutting the horizon at right angles. 

What is the Azimuth of an object in the heavens ? 

It is that part of the horizon contained between a 
vertical circle passing through the body, and the north 
or south points of the horizon. 

What is a Prime Vertical 7 

It is that azimuth circle which passes through the 
east and west points of the horizon. 

What is the Altitude of a heavenly object? 

It is the distance from the object to the horizon, 
reckoned on a vertical circle. 

What is the Zenith Distance of a heavenly body % 
2* 



L8 

It is tae distance from the body to the 'zenith, 
reckoned on a vertical circle. 

What is the Polar Distance of an object ? 

It is its distance from the pole, reckoned on a 
meridian. 

What is the Amplitude of a heavenly body 7 

It is the distance which it rises from the east, or 
sets from the west point of the horizon. 

What is Twilight 7 

It is that faint light, which appears before the sun 
rises and after it sets. 

What is the Diurnal Arch 7 

It is the course described by any body from its rising 
to its setting. 

What is the Nocturnal Arch 7 

It is the course described by any body from its set- 
ting till it rises again above the horizon. 



SECTION VI. 

Of the Tropics. 

What are the Tropics 7 

They are two small circles parallel to the equator, at 
about twenty-three degrees and a half from it. 

Through what points do they pass ? 

Through the solstitial points. 

What are they called ? 

The northern is called the Tropic of Cancer. 

The southern, the Tropic of Capricorn. 

What do they limit? 

They limit the sun's declination, because when it 
arrives at one of them it turns towards the other. 

When does a place have a vertical sun ? 

When the sun is directly over that place. 

What places have a vertical sun ? 



19 

Those only which are within the tropics ; and thoso 
have a vertical sun twice every year. 



SECTION VII. 

Of the Polar Circles. 

What are the Polar Circles 7 

They are two small circles described round the 
poles at the distance of about twenty-three degrees and 
a half from the poles, and parallel to the equator. 

What is their diameter ? 

About 47 degrees. 

What are they called ? 

The one described round the north pole is called the 
northern or arctic circle ; the other the southern or 
antarctic circle. 

How far are they distant from each other, from the 
equator, and from the tropics ? 

1. From each other 133 degrees* 

2. From the equator 66^ degrees. 

3. From the tropics 43 degrees. 



SECTION VIII. 

Of the Zones. 

What is a Zone 7 

It is a portion of the surface of the earth contained 
within the polar circles, or between two small circles 
parallel to the equator. 

How many zones are there ? 

There are jive, one Torrid, two Temperate, and 
two Frigid Zones. 



20 

What is the Torrid Zone 7 

It is the space included between the two tropics, and 
the equator passes through the middle ol it. 

How wide is it ? 

About 47 degrees, or 23i degrees each side of the 
equator. 

What are the principal countries in the torrid zone ? 

The southern part of North America, the northern 
half of South America, the West India Islands, the 
East India Islands, a great part of Africa, the southern 
parts of Arabia, Hindostan, and China, and the northern 
part of New Holland. 

How many Temperate Zones are there ? 

Two ; Northern and Southern. 

Describe the north temperate zone ? 

It is that space included between the northern tropic 
and north polar circle. 

How wide is it 1 

About 43 degrees. 

What are the principal countries in it ? 

The United States, East and West Florida, New 
Mexico, most of the British possessions in North Ame- 
rica, the north part of Africa, nearly all of Europe, 
Persia, and a great part of China, and Russia in 
Asia. 

Describe the southern temperate zone. 

It is that space included between the southern tropic 
and south polar circle. 

How Wide is it 1 

About 43 degrees. 

What are the principal countries in it ? 

New-Zealand, the southern part of South America, 
the Cape of Good Hope, and southern part of New 
Holland. 

Describe the North Frigid Zone. 

It is that space included within the north polar circle, 
having the north pole for its centre. 



21 

How wide is it ? 

About 47 degrees. 

What countries are in it 7 

Spitzbergen, and the northern extremities of North 
America, Europe, and Asia. 

What is said of its day and night ? 

The places directly under the poles have continnal 
day for six months, while the sun is north of the equa- 
tor, and continual night for the six months it is south 
of the equator. And all the places in this zone have 
their day longer or shorter according as they are near 
to, or distant from the pole. 

What is the South Frigid Zone ? 

It is that space included in the south polar circle. 

How wide is it ? 

About 47 degrees 

What is said of its day and night ? 

They are the same as in the north frigid zone, only 
it is night when the sun is north of the equator, and 
day when it is south of the equator. 

What are the Atwphiscii ? 

They are the inhabitants of the torrid zone, so called 
because they cast their shadows both north and south 
at different times of the year. 

What are the Heteroscii ? 

It is a name given to the inhabitants of the temperate 
zones, because at noon they cast their shadows only 
one way during the year. 

What are the Periscii ? 

It is a name given to the inhabitants of the frigid 
zones, because during one revolution of the earth on 
its axis, their shadows are directed to every point of 
the compass. 

What are the Antceci ? 

They are those who live under the same meridian, 
and have equal degrees of latitude ; but one has north 
latitude, and the other south latitude ; but when it is 
winter with one, it is summer with the other. 



22 

What are the Periceci 7 

They are those who live in the same latitude, but in 
opposite longitudes ; when it is noon with one, it is 
midnight with the other. 

What are the Antipodes 7 

They are those inhabitants of the earth who live 
diametrically opposite to each other, so that the feet 
of one point towards the feet of the other. — Their lati- 
tudes, longitudes, seasons of the year, days and nights, 
are all contrary to each other. 

What is a Climate 7 

It is a part of the surface of the earth contained 
between two parallels of latitude ; it diminishes in 
breadth towards the polar circles. 

Why have places in the same climate different tem- 
peratures 1 

These differences are produced by the influence of 
woods, lakes, mountains, sandy deserts, &e. upon the 
atmosphere. 



PART II. 
THE SOLAR SYSTEM. 

SECTION I. 

What is a System ? 

It is a supposed arrangement of the heavenly bodies. 

What is a Solar System ? 

It is that arrangement of the heavenly bodies, which 
places the sun in the centre, and the other bodies 
revolving round it. 

How many systems have there been, which are 
much known ? 

Three — the Ptolemaic, Tychonic, and Copemican. 

Describe the Ptolemaic ? 

The system was supported by Ptolemy; he supposed 
the earth to be placed in the centre of the system, and 
all the heavenly bodies to revolve round it from east 
to west. 

How many revolutions did he suppose the heavenly 
bodies to have ? 

Two — their daily revolution from east to west ; and 
another annual revolution round the earth. 

Describe the Tychonic. 

Tycho supposed with Ptolemy that all the heavenly 
bodies had a diurnal and annual revolution round the 
earth. 

How did he improve the system of Ptolemy ? 

By supposing likewise that all the planets, except 
the earth, revolved round the sun. 

What is the Copemican System ? 

It is the system supported by Copernicus, and is the 
true solar system. 



24 

What does it suppose ? 

It supposes tb3 sun to be placed in the centre of the 
system, and all the planets to revolve around it. 

How does it account for the apparent revolution of 
the heavenly bodies round the earth? 

By supposing a real rotation of the earth on its axis 
from west to east. 

What is Diurnal Revolution ? 

It is the revolution of a body on its axis, and is called 
its day. 

What is Annual Revolution ? 

It is the revolution of a body in its orbit round the 
sun, and is called its year. 

What is the Disc of the sun or a planet ? 

It is the circular illuminated surface which we see. 

}Yha.t is a Digit? 

It is a twelfth part of the apparent diameter of the 
disc. 

What is Quadrature 7 

A body is in quadrature with the sun, when the 
sun and body are ninety degrees distant from each 
other. 

What is Opposition ? 

A body is in opposition with the sun, when the sun 
and body are on opposite sides of the earth. 

How many kinds of Conjunctions are there? 

Two — Inferior and Superior. 

What is Inferior Conjunction ? 

It is when the body is between the earth and the 
sun. 

What is Superior Conjunction ? 

It is when the body and earth are on opposite 
sides of the sun. 

What is the Occuliation of a star or planet ? 

It is when they are hidden from the sight by the 
interposition of the moon or some other planet. 

What is Centripetal force? 



25 

It is that force which urges a body towards the centre 
or body round which it is revolving. 

What is Centrifugal Force 7 

It is that force with which a body endeavours to 
recede from the centre or body round which it is 
revolving. 

How are the heavenly bodies divided 1 

Into two kinds — Luminous and Opaque. 

What is a Luminous Body 7 

It is a body which shines by its own light. The 
sun, and perhaps the fixed stars, are luminous bodies. 

What is an Opaque Body 7 

It is that which shines by reflected light, or light 
received from the sun. 

Wliat is a Planet 7 

It is an opaque body which revolves round the sun. 

EIow are the planets divided ? 

Into two kinds — Primary, and Secondary, or Satel- 
lites. 

What is a Primary Planet 7 

It is that which revolves round the sun only. 

What is a Secondary Planet 7 

It is that which revolves round its primary, and with 
it round the sun. 

What is the shape of these planets % 

They are Oblate Spheroids,or flattened at the poles. 

How are they known to be Oblate Spheroids 7 

By observations with a telescope. 

What is the Transit 7 

It is the passage of a planet over the sun's disc. 

What are Asteroids 7 

They are small bodies which revolve round the sun, 
and are much smaller than the planets. 

What are Comets 7 

They are bodies revolving round the sun in very 
irregular orbits. Their number is not known. 

How do you distinguish them ? 

By a fiery train on the side from the sun. 
3 



26 



Of what is the solar system composed ? 

Of the Sun, Planets, Asteroids, Comets, and Stars. 



SECTION II. 

Of the Sun. 

What is the Sun 7 

The sun is a luminous body, and is placed in the 
centre of the system, with all the planets revolving 
round it at unequal distances. 

What does it afford to the other bodies ? 

It affords light, and perhaps heat and motion. 

What do some suppose it to be ? 

They suppose it to be a large opaque body, sur- 
rounded by an extremely brilliant atmosphere, which 
has the power of diffusing particles of light throughout 
the system. 

What is the Velocity of Light 7 

It moves 200,000 miles in a second. 

What is the Diameter of the sun ? 

It is 883,246 miles. 

How many revolutions has it ? 

Two — one on its axis, in 25 days 14 hours 8 
minutes, and another in its orbit round a supposed 
centre. 

How is its revolution on its axis determined ? 

From the spots on its surface, which appear first one 
side and then move over to the other side, and after 
being absent 12 days 7 hours, re-appear where they 
were first seen. 

What is the nature of these spots 7 

There are various opinions of them. Dr. Herschel 
thinks they are caused by some interruption in the 
lucid atmosphere, which leaves the opaque body of 
the sun open to our view. 



27 

SECTION III. 

Of the Planets. 

How many Primary Planets are there 1 

Seaem? Mercury, Venus, the Earth, Mars, Jupiter, 
Saturn, and Humufa u L WHANGS -f Ufc^T^ 

How many Secondary Planets are there ? 

Eighteen: the earth has one called the moon, Jupiter 
has four, Saturn seven, and Herschel six. 

Of Mercury. 

Which is the smallest of the planets ? 

Mercury is the smallest and nearest the sun. 

What is its diameter 1 

It is 3200 miles. 

What is its Distance from the sun 1 

It is 36,000,000 miles. 

How many revolutions has Mercury? 

It is not known for certainty to have more than one, 
and that is its revolution round the sun. 

What is the time of this revolution ? 

It is 87 days 23 hours, or about 88 days. 

What is said of the light and heat of Mercury 1 

They are about seven times greater than those of the 
earth. 



SECTION IV. 



Of Venus. 

What is the Diameter of Venus ? 
It is 7,687 miles, being the smallest except Mereuiy 
and Mars. 



28 

What is its distance from the sun ? 

It is 68,000,000 miles. 

What is the time of its rotation on its axis ? 

About twenty-three and a half hours. 

What is the time of its annual revolution ? 

About 224 days. 

When is it called the morning star ? 

When it is in the upper part of its orbit, and rises 
before the sun. 

When is it called the evening star ? 

When it passes round into the lower part of its orbit, 
and sets after the sun. 

What are its light and heat ? 

About double those of the earth. 

How are the light and heat of any planet increased 
or diminished ? 

According as it is nearer to the sun or farther from 
it ; Mercury will therefore have the greatest, and 
Herschel the least, of any of the planets. 

How are the primary planets divided? 

Into Inferior and Superior. 

Which are the Inferior ? 

Mercury and Venus ; and the Superior are Mars, 
Jupiter, Saturn, and Herschel. 

Why are they so divided ? 

Mercury and Venus are called inferior because their 
orbits are less than that of the earth. The other four 
are called superior, because their orbits are greater than 
that of the earth. 

Why do Mercury and Venus never have opposition ? 

Because the earth cannot pass between them and 
the sun. 

What peculiar variations have they ? 

Inferior conjunction and superior conjunction. 

Why can neither of the other four planets have 
inferior conjunction ? 

Because neither of them can pass between the earth 
and sun. 



29 



How do you know Mercury and Venus to te 
opaque bodies 1 

Because when they pass between us and the sun, 
and the side not illuminated by the sun is presented to 
us, they appear dark, which would not be the case it 
they were luminous bodies. 



section v. 
Of the Earth, 

What is the earth ? 

It is a spherical body. 

How is it known to be a spherical body ? 

First ; such a figure is best adapted to motion. 
Second ; navigators have sailed round it, which they 
could not do if it were not spherical. Third ; its 
shadow on the moon in a lunar eclipse is spherical. 

Is the earth a perfect sphere ? 

It is an oblate spheroid, or flattened at the poles. 

What is its diameter ? 

It is 7,919 miles.* 

Which is its greatest diameter ? 

The Equatorial Diameter is 25 miles greater than 
the Polar Diameter* 

What is its circumference ? 

About 24,877 miles.* 

What is its distance from the sun ? 

About 96,000,000 miles. 

How does it perform its Diurnal Rotation ? 

From west to east once in 24 hours. 

What is the period of its Annual Revolution 7 

About 365 days 6 hours. 

What is its hourly motion in its orbit 1 

It is 67,000 miles. 

♦These numbers are taken from the tables of Professor Adrain, 

3* 



30 

With what is the earth surrounded 

With an invisible fluid called air. 

What is the Atmosphere ? 

It consists of the air, with the vapours and other 
substances floating in it. 

Is air a simple or compound fluid ? 

It is compound, and is composed of oxygen and 
nitrogen. 

In what proportion ? 

About three fourths of nitrogen and one fourth of 
oxygen. 

How do they differ ? 

Oxygen is heavier than nitrogen, and supports life. 
heat, and vegetation ; nitrogen destroys them. 

What is the weight of air? 

It is 900 times lighter than water. 

What other fluid contains oxygen ? 

Water is composed of 85 parts oxygen and 15 of 
hydrogen. 

What is Wind? 

A current of air put in motion. 

What is the Cause of its motion ? 

When the air is rarefied by the heat of the sun it 
becomes light, and the heavier surrounding air rush- 
ing in produces wind. 

Why then does the wind change its direction ? 

It is owing to the change of the sun's place, to the 
influence of mountains, valleys, oceans, <fcc. 

How are the winds divided? 

Ino Monsoons, Trade, and Variable Winds. 

Describe the Monsoons. 

The monsoons, or shifting trade winds, are those 
which blow one half the year from the south-west, and 
the other half from the north-east. 

Where do they prevail ? 

In the Indian Ocean. 

Describe the Trade Winds. 



31 

They are those winds which always blow in the 
same direction ; on the north side of the equator from 
the east and north-east, on the south side from the east 
and south-east. 

Where do they prevail ? 

In the Atlantic and Pacific oceans, between the 
equator and 25 degrees of north and south latitude. 

What are Variable Winds ? 

Those which are continually changing from day 
to day, owing to the inequality of the earth's sur- 
face. 

Where do they prevail 1 

Beyond the 40th degree of latitude. 

What are land and sea Breezes ? 

Those which blow a certain number of hours from 
the land and then a certain number of hours from the 
sea. They prevail in the torrid zone. 

What are Vapours ? 

They are fdrmed by watery particles separated from 
the land or water by the action of the sun ; being light- 
er than the air, they rise and float in it. 

What are Clouds ? 

They consist of vapours exhaled from the sea or 
land ; when these vapours rise to a height where their 
density is equal to the surrounding air, they unite and 
become heavier. 

What is Rain 7 

When clouds become so condensed and heavy that 
the air cannot support them, they descend in the form 
of rain. 

Where does the most rain fall during the year 1 

At the equator ; because the heat of the sun being 
there the greatest, produces the greatest exhalations. 

What is Snow ? 

It is composed of vapours frozen while small, and 
being but little heavier than the air, descend with a 
gentle motion to the earth. 



32 

What is Hail ? 

It is composed of vapours condensed into drops, and 
by some sudden change in the atmosphere are frozen 
while falling. 

What are Fogs and Mist ? 

They are thin clouds resting on the surface of the 
earth. 

Have the other planets an atmosphere ? 

They are supposed to have. 



SECTION VI. 

Of Mars. 

What is the diameter of Mars 1 

It is 4189 miles, being the smallest except Mer- 
cury. 

What is its distance from the sun ? * 

It is 144,000,000 miles. 

What is the time of its annual revolution 7 

One year and 321 days. 

What is the time of its diurnal rotation ? 

About 24 k hours. 

By what is Mars distinguished from the other pla- 
nets ? 

By a red fiery colour. 



SECTION VII. 

Of Jupiter. 

What is the diameter of Jupiter ? 

It is 89,170 miles, being the largest planet 

What is its distance from the sun ? 



33 

It is 491,700,000 miles. 

In what time does it revolve on its axis 7 . 

About ten hours. 

In what time does it revolve round the sun 7 

In eleven years 314 days. 

By what is Jupiter distinguished. ? 

By faint substances called belts, which surround it. 



SECTION VIII. 

Of Saturn. 

What is the Diameter of Saturn ? 

ft is 79,000 miles, being the largest except Jupiter, 

What is its Distance from the sun ? 

It is 901,000,000 miles. 

In what time does it revolve on its axis 7 

In about ten hours. 

What is the time of its Annual Revolution ? 

It is 29 years and about a half. 

By what is it distinguished ? 

By a large ring of solid matter which surrounds it. 



SECTION IX. 

Of Herscheh 

When was this planet discovered 1 

In 1781, by Dr. Herschel. 

"What is its Diameter 1 

It is 35,000 miles. 

What is its Distance from the sun I 



34 

It is 1800,000.000 miles. 

In what time does it revolve on its axis 1 

It is not discovered whether it revolves on its axte. 

In what time does it revolve round the sun ? 

In S3 years 150 days. 



section x. 

Of the Moon. 

What is the Moon ? 

It is a satellite of the earth. 

What is its diameter ? 

It is 2180 miles. 

What is its distance from the earth ? 

About 240,000 miles. 

In what time does it revolve around the earth ? 

In about 27 1-2 days, about 2,300 miles an hour 

In what time does it revolve on its axis ? 

About 29 1-2 days. 

When is it New Moon ? 

When the moon is in conjunction, or between the 
earth and the sun, and the dark side is presented to us. 

When is it Full Moon 7 

When the moon is in opposition, or when the earth 
is between the sun and moon, and the illuminated side 
is presented to us. 

Does the moon rise at the same hour every evening? 

It rises about an hour later every successive evening. 

What is Harvest Moon ? 

When the moon is full in September and October, 
it rises immediately after sunset for several days in 



35 

succession, and thus affords light for collecting the 
harvest, and is therefore called harvest moon. 



SECTION XI 

Of the Tides. 

What is Tide 7 

It is the rising and falling of the waters in oceans 
and rivers. 

How is it caused 1 

By the attraction of the sun and moon acting upon 
the water. 

How are the tides divided ? 

1. Into Flood and Ebb tides. 

2. Into Spring and Neap tides, 
What is flood tide 1 

It is when the water is rising. 

What is ebb tide ? 

It is when the water is falling. 

How often do the flood and ebb tides happen 1 

Twice in each day. 

What is spring tide ? 

It is the greatest flood and ebb tide. 

When does it occur ? 

When the sun and moon are exactly on the same or 
opposite sides of the earth, and unite their attraction to 
raise water to its greatest height on opposite sides of 
the earth, and depress it to its lowest ebb 90 degrees * 
distant from those points. 

What is neap tide ? 

It is the least flood and ebb tide, and occurs when 
the sun and moon are in quadrature, and their attract- 
ing forces counteract each other. 



36 

How often do the spring and neap tides occur ? 

Twice in each lunar month, at new and full moon. 

How do the sun and moon differ in their attraction ? 

The attraction of the moon upon the water is three 
times as great as that of the sun ; the tide will, 
therefore, be highest directly under the moon. 

Why does the moon attract the water more than the 
sun does ? 

Because it is so much nearer the earth than the sun 
is. 

Why does the tide rise nearly an hour later each 
successive day 1 

Because the moon revolves round the earth from 
west to east, and moves forward in its orbit nearly an 
hour in each day. 

What have been discovered in the moon ? 

Mountains, volcanoes, valleys. &c. 



SECTION XII. 

Of Eclipses. 

What is an Eclipse 7 

It is the interception of the rays of light by some 
opaque body passing between the sun and the eclipsed 
body. 

How are the eclipses divided ? 

1. Into Solar and Lunar. 

2. Into Total and Partial. 
What is a Solar Eclipse 7 

It is an eclipse of the sun ; it happens only at new 
moon, and is caused by the moon passing between 
the earth and sun, and concealing the sun from our 
view. 

What is a Lunar Eclipse ? 



37 

It is an eclipse of the moon ; it can happen only 
at full moon, and is caused by the earth passing be- 
tween the sun and moon, and casting a shadow upon 
the moon's disc. 

What is a Total Eclipes 7 

It is when the whole of the disc of the sun or moon 
is concealed. 

What is a Partial Eclipse ? 

It is when only a part of the sun or moon is con- 
cealed. 

What is the greatest number of eclipses that can 
happen in a year ? 

Seven ; and in that case five will be solar and two 
lunar. 

What is the least number that can happen in a 
year? 

Two ; and these must both be solar. 



SECTION XIII* 

Of the Fixed Stars. 

What are Fixed Stars? 

They are those which appear to be always in the 
same situation with respect to each other. 

What is the Distance of the nearest fixed star ? 

It is supposed to be so far distant, that a ball going 
500 miles an hour would not reach it in two millions 
of years. 

What is the Magnitude of the fixed stars 7 

They are supposed to be as large as the sun. 

Are they luminous or opaque ? 

They are supposed to be luminous, or to shine by 
their own light. 

Why are they supposed to be luminous bodies ? 

For two reasons ; 1. If they shine with reflected 
4 



38 

light, they could not be seen at such an immense 
distance. 

2. If they borrowed their light from any lumi- 
nous body near them, that body would itself be 
visible. 

What is a Constellation 7 

It is several stars included in a certain space. 

What is the meaning of Nebulous or Cloudy 7 

It is a term applied to those clusters of irtars which 
are so near together and so far distant that they appear 
like thin clouds. 

What is the Galaxy or Milky Way 7 

It is a vast number of stars arranged so near to 
gether as to appear like clouds. 

What is the number of constellations ? 

About ninety. 



SECTION XIV. 



A Table of the Magnitudes, Distances, and Revolu 
tions of the planets, in round numbers. 



Names. 


Diameters. 


Sun. 

Mercury, 

Venus, 


883,000 
3,200 

7,687 


Earth, 


7,950 


Mars, 
Jupiter, 
Saturn, 
Herschel, 


4,189 
89,170 
79,000 
35,000 



Distance from the 
• Sun. Miles. 


Revolution 

round the Sun. 

Y. D. 


36,000,000 




88 


68,000,000 




224 


96,000,000 

144,000,000 

491,700,000 

901,000,000 

1800,000,000 


1 
11 

29 
83 


365 
321 
314 

178 
150 



Revolution 

on its axis. 

Hours 



23i- 

24 

24J- 

10 

10 



How many Asteroids are there ? 
Four ; all revolving round the sun in orbits between^ 
the orbits of Mars and Jupiter. 



39 

Table of the Asteroids. 



Names. 



Diameters. 

Miles. 



Distance from the 
Sun.- 



Revolution rouni 
the Sun. 



Y. 

4 
4 
4 
3 



D. 

222 
222 
130 
240 



Ceres, 1621,161 263,000,000 
Pallas, 2092,110 266,000,000 
Juno, 1425 253,000,000 

Yesta, ' 225,000,000 

What is the nature of the above planets and as- 
teroids ? 

Mountains and valleys, &c. have been discovered 
on the Moon and Venus ; hence we infer the same of 
the other planets, and that they have oceans, dry land, 
<fec. and may be inhabited. 



SECTION xv. 



Of Maps. 

What is a Map 7 

It is a delineation of the earth's surface on a 
plane. 

How does a map differ from a globe ? 

In the same manner as a picture differs from a 
statue. 

How do you know the directions on a map ? 

The upper end is north, the lower end south, the 
right hand east, and the left hand west. 

How are the latitude and longitude found on a 
map ? 

The figures on the east and west side of a map 
show the latitude, and the figures on the north and 
south side shaw the longitude. 

How are the several objects represented on a 
map? 

Roads are represented by double lines. 



40 

Rivers, by black lines increasing towards the mouth 
of the rivers. 

Lakes, by a dark colour the shape of the lake. 

Sands and shallows by dots close together. 

Bays and gulfs, by arms of the ocean or sea running 
up into the land. 



SECTION XVI. 

Of Globes. 

What is a Globe ? 

It is a round body. 

How many kinds of globes are there 1 

Two — Terrestrial and Celestial. 

What does the terrestrial globe represent ? 

The figure of the earth, with its oceans, continents, 
rivers, kingdoms, &c. , delineated on its surface. 

What is represented on the celestial globe ? 

On its surface are delineated all the appearances of 
the heavens. 

In viewing the representations on these globes, 
where is the eye supposed to be placed ? 

On the surface of the terrestrial globe, and at the 
centre of the celestial. 



PART III. 



PROBLEMS PERFORMED 

BY THE 

TERRESTRIAL GLOBE. 



PROBLEM I. 

To find the latitude of any given place. 

Rule — Bring the place to the graduated side of the 
brazen meridian, and the degree of the meridian over 
the place is the latitude. 

1. What is the latitude of London ? Ans. Fifty- 
one and a half degrees north. 

2. What is the latitude of St. Helena? About 
sixteen degrees south. 

3. What places have no latitude ? 
Those directly under the equator. 

4. Find all the places which have no latitude. 

5. All places between the equator and south pole 
are in south latitude, and those between the equator 
and north pole are in north latitude. 

6. Find the latitude of the following places. 



Amsterdam, 


Dublin, 


Norfolk, 


Aleppo, 


Edinburgh, 


Paris, 


Athens, 


Fez, 


Philadelphia, 


Algiers, 
Bengal, 


Halifax, 


Prague, 


Ispahan, 


Quito, 


Boston, 


Lima, 


Rome, 


Batavia, 


Lisbon, 


Stockholm, . 


Cape of Good Hope, 


Madrid, 


Tenerirle, 


Cape Horn, 


Madras, 


Tripoli, 


Cairo, 


Moscow, 


Washington, 


Dantzic, 


New York, 


Vienna. 


' 4* 







42 



PROBLEM II. 



To find the longitude of any given 'place. 

Rule — Bring the place to the brazen meridian, and 
the degree of the equator under the meridian, is the 
longitude. 

1. What is the longitude of Washington? About 
seventy-seven degrees west. 

2. What is the longitude of Madras? Eighty 
degrees east. 

3. What is the greatest longitude a place can 
have? 

It is one hundred and eighty degrees. 

4. How do you find all those places which have the 
greatest longitude ? 

Bring the one hundred and eightieth degree of the 
equator to the meridian, and all the places under the 
meridian have the greatest longitude. 

5. Find the longitude of the following places. 



Alexandria, 


Gibraltar, 


Portsmouth, 


Archangel, 


Havanna, 


Quebec, 


Aleppo, 


Hamburgh, 


Rhodes, 


Albany, 


Buenos Ayres, 


Syracuse, 


Baltimore, 


Knoxville, 


Rio Janeiro, 


Berlin, 


London, 


Caraccas, 


Constantinople, 


Leghorn, 


Sierra Leone, 


Charleston, 


Jerusalem, 


Tunis, 


Canton, 


Montreal, 


Tyre, 


Calcutta, 


New Orleans, 


Toulouse, 


Cadiz, 


Nankin, 


Vesuvius, 


Delhi, 


Oporto, 


Venice, 


Dresden, 


Pekin, 


Warsaw, 


Damascus, 


Petersburgh, 


Washington. 



43 



PROBLEM III. 



To find any place whose latitude and longitude art 
given. 

Ruta — Bring the longitude of the place to the 
brazen meridian, and under the given latitude will be 
the place required. 

1. What is the place whose east longitude is thirty 
degrees, and its north latitude thirty-one degrees? 
Ans. Alexandria. 

2. What is the place in about six degrees west lon- 
gitude, and sixteen degrees south latitude? Ans. 
St. Helena. 

3. Find those places which have the following lati* 
tudes and longitudes. * 



Latitude. 




Longitude 




56 deg 


. South, 


67deg 


. West, 


40 


North, 


116 


East, 


43 


North, 


79 


West, 


52 


North, 


5 


East, 


31 


N. 


30 


E. 


52.^ 


N. 


13 


E. 


30 


N. 


31 


E. 


34 


S. 


18 


E. 


49 


N. 


2 


E. 


42£ 


N. 


71 


W. 


5 


N. 


52 


w. 


41 


N. 


29 


E. 


51* 


N. 




E. 


12 


S. 


77 


W. 


33 


N. 


36 


E. 


30 


N. 


90 


W 



Note.— -The degrees without the minutes are given, as being siiiH 
piently accurate for all operations on the globe. 



44 



PROBLEM IV. 



To find all those places that are in the same latitude 
or longitude of any given place. 

Rule — Bring the given place to the brazen meridi- 
an ; then all the places under the meridian are in the 
same longitude ; turn the globe round, and all the 
places that pass under the latitude of the place are in 
the same latitude. 

1. What places have nearly the same longitude as 
New York ? 

Ans. Montreal, St. Martha, Conception, &c. 

2. What places have the latitude of New York? 
Ans. Naples, Madrid, Pekin, &c. 

3. What places have the same longitude as the fol 
lowing places ? 

Paris, Boston, Cape de Verd, 

Archangel, Mexico, Cape Comorin, 

Naples, Gibraltar, Bermudas. 

4. What places have the latitude of the following 
places? 

London, Rome, Lima, Buenos Ayres. 

Petersburgh, Philadelphia, Lisbon, Halifax. 

5. What places have noon at the same time with 
Baltimore ? 

This is the same as finding all places that have the 
same longitude with Baltimore. 

6. What places have summer at the same time with 
Augusta in Georgia ? 

7. What places have winter at the same time with 
Buenos Ayres ? 



45 



PROBLEM V. 



To find the difference of Latitude between any two 
places. 



Rule — Find the latitude of both places, and the 
number of degrees between them, reckoned on the 
brazen meridian, is the difference of latitude. 

Note — If the places are on different sides of the equator, you add the 
two latitudes together : if on the same side of the equator, you subtract 
the less from the greater 

1. What is the difference of latitude between Lon- 
don and Madras ? Ans. Thirty-eight degrees. 

2. What is the difference of latitude between Boston 
and Cape Horn ? Ans. Ninety-seven and a half de 
grees. 

3. What is the difference in latitude between 
Copenhagen and Gibraltar. 

London and Cape of Good Hope, 

Bengal and St. Helena, 

Madrid and Moscow, 

New-Orleans and New- York, 

Montreal and Charleston, 

London and New- York, 

Pekin and Lima, 

Edinburgh and Baltimore, 

Calcutta and Philadelphia, 

Cape of Good Hope and Cape Horn, 

Dublin and Boston, 

Petersburgh and Vienna. 

Goa and Rome, 

Philadelphia and Jerusalem, 

The Azores and Spitzbergen, 

Falkland Islands and Newfoundland ? 



46 



PROBLEM VI. 

To find the difference of Longitude between any two 
places. 

Rule — Find the longitude of both places, and the 
number of degrees between them will be the difference 
of longitude. 

Note— If both places are east or both west longitude, substract the 
one from the other ; if the one is_east and the other west longitude, add 
them together. 

1. What is the difference of longitude between 
London and Constantinople ? Ans. Twenty-nine de- 
grees. 

2. What is the difference of longitude between 
Montreal and Lisbon ? Ans. Sixty-four degrees. 

3. What is the difference of longitude between 
Philadelphia and Constantinople ? Ans. One hundred 
and four degrees. 

4. What is the difference of longitude betv/een 
Acapulco and Lisbon, 

Madrid and Philadelphia, 

Cadiz and Batavia, 

Paris and Pekin, 

Cape Horn and Botany Bay, 

Cape Cod and Venice, 

Havana and Algiers, 

New- York and Canton ? 

5. If the sum of the longitudes exceed one hundred 
and eighty, substract it from three hundred and sixty ; 
the remainder will be the difference of longitude ; as, 

Acapulco 101 o West, 
Pekin 116= East, 



217—143. diff. of longitude. 



47 



PROBLEM VII. 



The hour of the day at any place being given, to 
find what o'clock it is at any other place. 



Rule — Bring the place, where the hour is given, 
to the brazen meridian ; set the index to the given 
hour, then turn the globe till the proposed place comes 
under the meridian ; the index will point to the hour 
required. 

•— -. • 

Note— 1. If the place required be to the east of the given place, it is 
later ; if to the west, it is earlier. 

Note— 2. If the place required be east of the given place, turn the 
globe westward : if to the west, turn the globe eastward. 

1. When it is twelve o'clock at noon in London, 
what is the time at Mauritius and Philadelphia ? 

Ans. Four P. M. at Mauritius, and seven A. M. at 
Philadelphia. 

2. When it is 8 o'clock A. M. at Boston, what is the 
time at Acapulco and Cape Farewell? 

Ans. Six A. M. at Acapulco, and ten A. M. at Cape 
Farewell. 

3. When it is midnight at New-York, what o'clock 
is it at 

Paris, Canton, New-Orleans, 

Rome, Calcutta, Rio Janeiro, 

Petersburgh, Cairo, Ascension Island ? 

4. When it is noon at Lisbon, what is the hour at 

Quebec, Jerusalem, St. Helena, 

Mexico, Cape Comorin, Botany Bay, 

Cape Horn, Pekin, Athens, 

Bermudas, Babelmandel, Tripoli? 



48 



PROBLEM VIII. 



The hour of the day being given at any place, to fina 
all the jAaces on the globe where it is any other 
given hour. , 



Rule — Bring the place to the brazen meridian, and 
set the hour of the index at that place ; turn the globe 
till the index points to the other given hour, then all 
the places under the brazen meridian are the places 
required. 

1. When it is twelve at noon at London, at what 
places is it eight A. M. ? 

Ans. Cape Canso, Martinico, Trinidad, &c. 

2. When it is 2 P. M. in London, where is it half 
past five P. M. 1 

Ans. Caspian Sea, Socofra, Madagascar, &c. 

3. When it is five A. M. at Madrid, where is it 
noon ? 

4. When it is noon at New- York, where is it five 
P. M. ? 

5. When it is ten A. M. at New- York, where is it 
noon ? 

6. When it is noon at Paris, where is it midnight ? 
.7. Does the sun rise first upon Cape Faiewell or 

New-Orleans? 

8. Does the sun set soonest at the Bermuda Islands, 
or the Gulf of California? 

9. What places have six o'clock A. M. when it is 
noon at the Falkland Islands ? 

10. When it is noon at Lisbon, at what place is it 
eight o'clock in the afternoon, and at what places is it 
six o'clock in the forenoon ? 



PROBLEM IX. 

Tefind the Antoeci of any place. 

Rule — Bring the given place to the brazen meridian, 
and find its latitude ; then in the same degree of lati- 
tude, on the other side of the equator, will be the 
Antosci. 

1. What is the Antoeci of the Bermudas 1 
Ans. Near the Cordova in Paraguay. 

2. What is the AntoBci of New- York 1 
Ans. Near the Island of Chiloe. 

3. What is the Antoeci of Madagascar 1 
Ans. Arabia. 

4. Required the Antosci of 

C. of Good Hope, Isthmus of Suez, Chesapeake Bay, 
Oape Horn, Labrador, Jeddo. 



problem x. 

To find the Periceci of any place. 

Rule — Bring the given place to the brass meridian, 
and set the index to twelve ; then turn the globe till the 
index comes to the other twelve, and under the latitude 
of the given place will be the Perioeci. 

1. What is the Perioeci of the Gulf of Mexico ? 
Ans. The Bay of Bengal. 

2. What is the Perioeci of the United States ? 
Ans. China. 

3. What is the Perioeci of England 1 
Ans. Near the Fox Islands. 

4. What is the Perioeci of the following places ? 
Lake Superior, Black sea, Chili, 
Baltimore, Gibraltar, Ceylon. 



50 

PROBLEM XI. 

To find the Antipodes of any place. 
Rule — Bring the given place to the Meridian, and 
find its latitude ; set the index to twelve, and turn the 
globe till the index points to the other twelve ; then 
the same degree of latitude on the other side of the 
squator shows the Antipodes, thus : 

1. What is the Antipodes of London % 
Ans. The south part of New Zealand. 

2. What is the Antipodes of the Bermudas ? 
Ans. South-west part of New Holland. 

3. What is the Antipodes of the Society Islands ? 
Ans. The Red Sea. 

4. What is the Antipodes of 

Cuba, Caspian Sea, Spain, 

Terra del Fuego, Egypt, Persia ? 

PROBLEM XII. 

To find the distance in miles between any two places 
on the globe. 
Rule — Lay the quadrant of altitude over both places, 
and it will show the number of degrees, which multi- 
ply by sixty-nine and a half, and it will give the dis- 
tance in miles. 

1. What is the distance between London and Ja- 
maica ? 

Ans. Sixty-seven and a half degrees, or four thou- 
sand six hundred and ninety-one miles. 

2. What is the distance between New- York and 
Paris? 

3. What is the distance between Baltimore and 
London ? 

4. What is the distance between 

Cadiz and Petersburgh, Washington and Madrid, 
Capes Horn and Good Hope, Philadelphia and Venice, 
New- York and London, Cuba and Cyprus, 
Charleston and Fez, London and Bombay? 



51 



PROBLEM XIII. 



The day of the month being given, to find the Sun's 
place or longitude in the Ecliptic, and its decli- 
nation. 

Rule — Look for the given day in the circle of 
months on the horizon, and opposite to it, in the circle 
of signs, are the sign and degree the sun is in on that 
day. Find the same sign and degree in the ecliptic, 
and it will be the sun's place or longitude ; bring this 
place to the meridian, and you will have the declination. 

1. What is the sun's longitude and declination on 
the 22d day of February ? 

Ans. Its longitude is three hundred and thirty-seven 
and a half degrees, or four and a half degrees, in Pisces: 
its declination is ten degrees south. 

2. What is the sun's longitude and declination on 
the 15th of April? 

Ans. Its longitude is twenty-five and a half degrees 
in Aries ; its declination ten degrees north. 

3. When does the sun enter each of the signs 1 
This question is answered in Part I. Sec. IV. 

4. What is the sun's declination on the 21st of 
June ? 

5. What is the sun's place and declination on the 
22d of December ? 

6. What is the sun's place in the ecliptic, and its 
declination, on each of the following days ? 



March 


30th, 


September 


16th, 


April 


4th, 


October 


5th, 


May 


12th, 


November 


2d, 


June 


9th, 


December 


29th, 


July 


13th, 


January 


7th, 


August 


8th, 


February 


18th. 



52 



'PROBLEM XIV. 



To rectify the globe for the Latitude, Zenith, and 
Slut's place on any day. 



1. For the Latitude. Elevate the pole till the 
horizon cut the brass meridian in the degree corres- 
ponding to the latitude of the place. 

2. The given place is then in the zenith. 

3. Then ( by Problem XIII.) find the sun's place 
for the given day, bring it to the meridian, and set 
the index to twelve. 

Note— If the place be in north latitude, elevate the north pole, if in 
south latitude, elevate the south pole. 

1. Rectifv the globe for the latitude of London on 
the tenth of May. 

In this case elevate the north pole fifty-one and a 
half degrees, then London will be in the zenith ; over 
it screw the quadrant of altitude ; the tenth of May 
on the horizon answers to the twentieth degree of 
Taurus, which find on the ecliptic, and bring it to the 
meridian, and set the index to twelve. This is the 
position of the globe as it appears to the inhabitants on 
the tenth of May. 

2. Rectify the globe for 

New- York, 12th January. 

Boston, 6th February. 
Constantinople, 9th March. 

Petersburgh, 10th April. 

Madrid, 16th September. 

Cape Horn, 15th November. 

St. Jago, (Chili) 14th December. 

Gailipagos, 19th October. 



53 



PROBLEM XV. 



The month and day of the month being given, to find 
all those places on the globe which will have a Verti- 
cal JSiin on that day. 



Rule — Find the sun's place on the ecliptic, (Prob. 
XIII. ) and bring it to the meridian ; turn the globe 
round, and all the places that pass under that degree 
of the meridian, have a vertical sun on that day. 

1. Find all the places which have a vertical sun on 
the twenty-second of February : 

Ans. Peru, Amazonia, Angola, New Guinea, Q,ueen 
Charlotte's Islands, &c. 

2. What places have a vertical sun on the ninth of 
May? 

3. What places will have a vertical sun on the 

21 st of March. 23 d of Sept. 

21st of June, 22dofDec? 



Note— Where the sun is vertical, the rains are almost continual, and 
cause the large rivers to rise. 



4. What large rivers will be affected by a vertical 
sun on the first of June ? 

5. What large rivers will be affected by a vertical 
sun on the first of March ? 

6. At what places will the rainy season commence 
on the twentieth of April ? 

7. What places will have a rainy season on the 
twentieth of October ? 

8. What seas will have a vertical sun on the ninth 
of May? 

5* 



54 

PROBLEM XVI. 

Tojtnd at what hour the sun rises and sets at any 
place, and dap in the year, a?id length of the day 
and night at that place. 

Rule— 1. Rectify the globe (by Problem XIV.) for 
the latitude of the place ; find the sun's place in the 
ecliptic (by Problem XIII.) and bring it to the meri- 
dian, and set the index to twelve ; bring the sun's place 
to the eastern edge of the horizon, and the index will 
show the hour of rising ; bring it to the western edge 
of the horizon, and the index will show the hour of 
setting. 

2. Double the time of sun rising, and it will give 
the length of the night ; double the hour of sun setting 
and it will give the length of the day. 

1. What time does the sun rise and set at New- 
York on the tenth of May, and what is the length of 
the day and night ? 

Ans. It rises fifty-six minutes past four ; sets four 
minutes after seven ; length of the night nine hours 
fifty-two minutes; of the day fourteen hours eight 
minutes. 

2. What is the time of sun rising and sun setting, 
and the length of the day and night, at each of the fol- 
lowing places, on the day mentioned ? 

Washington City, 4th of May. 

Constantinople, 14th of June. 

London, 15th of July. 

Rio Janeiro, Sth of September. 

Cape Horn, 1st of December. 

Rome, 5th of January. 

Naples, 9th of October. 

Canton, Sth of August. 

Boston^ 7th of November, 



55 



PROBLEM XVII. 



To find the length of the longest and shortest daps 
and nights in any yart of the world. (See Part I. 
Sec. IV.) 

Rule — 1. If the place be in the northern hemi- 
sphere, rectify the globe for the latitude of the place, 
bring the first degree of Cancer to the meridian, and 
proceed as in the last problem. 

2. If the place be in the southern hemisphere, bring 
the first degree of Capricorn to the meridian, and pro- 
ceed as before. 

1. What is the length of the longest day and shortest 
night at New York ? 

Ans. Longest day fourteen hours and fifty-six mi- 
nutes, shortest night nine hours and four minutes. 



Note— The shortest night of any place is equal to its shortest day, 
when the sun is on the other side of the equator, and its longest day 
to its longest night. 



2. What is the length of the longest day and shortest 
night at each of the following places : 



Boston, 


London, 


River Zaire, 


Philadelphia, 


Iceland, 


Botany Bay, 


Mexico, 


Cape Yerd, 


Madras, 


Halifax, 


Suez, 


Mouth of Colum- 


Quebec, 


Bombay, 


bia River, 


Augusta, 


Canton, 


Hudson's Bay, 


New Orleans, 


Madagascar, 


Dardanelles, 


Quito, 


Abo, 


Azores, 


. Chiloe, 


Berlin, 


Isles of Georgia 1 


The shortest t 


day and longest 


night are shown by 


the above note. 







50 



PROBLEM XVIII. 



The ?no?ith, and day of the month being given, to find 
those places where the sun does not set, and where it 
does not rise on the given day. (See Part I. Sect. 
IV.) 

Rule — Find the sun's declination (by Prob. XIII.) 
elevate the pole for the declination, in the same manner 
as for the latitude ; turn the globe on its axis, and on 
the places round the pole above the horizon the sun 
does not set ; and on the places round the other pole 
below the horizon, the sun does not rise on that day. 

1. How much of the south frigid zone is darkened, 
and how much of the north frigid zone is enlightened 
on the twentieth of May ? 

Ans. Twenty degrees round each pole. 

2. On which pole does the sun rise on November 
the sixth? 

3. Which frigid zone and how much of it has con- 
stant day on August fourth ? 

4. How much of the south frigid zone has constant 
day on the following days : 

October 1st, January 9th, 

October 20th, Feb. 10th, 

Nov. 19th, Feb. 20th, 

Dec. 22d, March 1st? 

5. What days in the year does the sun shine equally 
on both poles ? 



57 
PART IV. 

PROBLEMS PERFORMED 

BY THE 

CELESTIAL GLOBE, 



It may be proper here to repeat the following de- 
finitions : 

1. Latitude on the celestial globe is reckoned from 
the ecliptic, north and south. 

2. Longitude is reckoned on the ecliptic, from the 
first point of Aries round the globe, 

3. Declination is reckoned from the equinoctial 
north and south. 

4. Right Ascension is reckoned on the equinoctial 
from the first point in Aries round the globe. 



In order that the student may be able to find the 
several stars mentioned in the following problems, I 
have thought proper to subjoin a list of the constella- 
tions, with the principal fixed stars in each. 

1. Constellations in the Zodiac. 
Names. Principal Stars in each. 

1. o,o Aries Arietis. 

2. ft Taurus. Aldebaran, Pleiades, Hyudes. 

3. n Gemini. Castor and Pollux. 

4. £2 Cancer. Acubens. 

5. $\ Leo. Regulus and Deneb. 

6. it£ Virgo. SpicaVirginis fy Vindematrix. 

7. £; Libra. Zubenelg <$• Zebenesch. 



58 

8. m Scorpio. Ant ares. 

9. j Sagittarius. 

10. vj Capricornus. Capella. 

11. je Aquarius. Scheat. 

12. >f Pisces. 



2. Constellations north of the Zodiac. 



1. Ursa minor, the little bear. 

2. Ursa major, the great bear. 

3. Draco, the dragon. 

4. "Cepheus. 

5. Cassiopeia. 

6. Camelopardalus. 

7. Auriga, the charioteer. 

8. The Lynx. 

9. Leo minor, the little lion. 

10. Canes Venatici, the grey- 
hounds. 

11. Coma Berenices, Berenice's 

12. Bootes. 

13. Corona Borealis, northern 
crown. 

14. Hercules. 

15. Lyra, the harp. 

16. Cygnus, the swan. 

17. Vulpecula et Anser, the 
fox and the goose. 

18. Sagitta, the arrow. 

19. Delphin, the dolphin. 

20. Equuleus, the little horse. 

21. Pegasus, the flying horse. 

22. Lacerta, the lizard. 

23. Andromeda. 

24. Triangulum, the triangle. 



Abruccabur. 

Alioth. 

Rastaben. 

Alderamin. 

Schedar. 

Capella. 



Cor. Caroli. 



hair. 
Arsturus Mirach. 

Alphecca. 
Has Algethi. 
Vega, Lyra. 
De?ieb, Albirco. 



Markab Sheat. 
Algenib. 

Mirach Almaach. 



59 

25. Musca Borealis, the north- 
ern fly. 

26. Perseus et caput Medusae, 

head of Meduso. Angol. 

27. Serpens, the serpent. 

28. Ophincus vel serpentarius. Ras. Alhag-us, 

29. Taurus Poniatouski, Poni- 
aiouski's bull. 

30» Aquila, the eagle. Atair, 

3. Southern Constellations. 

Names. Principal.Stara. 

1. Cetus, the whale. Menkar. 

2. Eridanus, the river Po. Achernar. 

3. Orion. Betelguese, Rigel, 

4. Monoceros, the unicorn. 

5. Canis minor, the little dog. Procyon, 

6. Sextans, the sextant. 

7. Crater et Hydra, the cup 
and Hydra. 

8. Corvus, the crow Algorab. 

9. Centarus, the centaur. A bright star* 

10. Lupus, the wolf. 

11. Norma, the rule. 

12. Circinus, the compasses. 

13. Triangulum australe, the 
southern triangle. 

14. Ara, the altar. 

15. Telescopium, the telescope. 

16. Corona Australis, the south 
crown. 

17. Indus, the Indian. 

18. Microscopium, the micro 
scope. 

19. Piscis Australis, southern 

fish. Fomalhaut. 

20. Grus, the crane. 



60 

21. Toucana, the American 
goose. 

22. Phenix. 

23. Apparatus sculptoris, the 
sculptor's apparatus. 

24. Fornax, the furnace. 

25. Horologium, the clock. 

26. Cela sculptoria, the en- 
graver's tools. 

27. Lepus, the hare. 

28. Canis Major, great dog. Sirius. 

29. Columba, the dove. 

30. Equuleus pictoreus. 

31. Argo navis, the ship Argo. Canopus. 

32. Pixis nautica, tlie mariner's 
compass. 



The following table shows in what part of each con- 
stellation the principal stars are placed. 

Aldebaran, in the south eye of Taurus. 

Acubens, in the claw of Cancer. 

Antares, in the heart of Scorpio. 

Abruccabar, the pole star in the tail of the little 
Bear. 

Alioth, the first star in the tail of the great Bear. 

Arcturus, in Bootes. 

Alphecca, the bright star in the northern crown. 

Almaach, in the foot of Andromeda. 

Algol, in the head of Medusa. 

Atair, the bright star in the Eagle. 

Achernar, in the river Eridanus. 

Betelgeux, in the east shoulder of Orion. 

Bellatrix, in the west shoulder of Orion. 

Castor and Pollux, in the head of Gemini. 

Capella, the bright star in Capricorn. 

Cor. Caroli. the double star in the greyhounds. 



61 

Canopus, the bright star in Argo. 
Deneb, in the tail of the swan. 
Fomalhaut, bright star in the southern ftsh. 
Hyades, in Taurus. 
Mirach, in the thigh of Bootes. 
Markab, in the wing of Pegasus. 
Mirach, in the girdle of Andromeda. 
Menkar, in the jaw of the whale. 
Pleiades, the brightest star in Taurus. 
Procyon, bright star in the little Dog. 
Regulus, in the heart of Leo. 
Rastaben, in the head of the dragon. 
Has. Algithi, in the head of Hercules. 
Ras. Alhagus, in the head of Ophincus. 
Rigil, in the foot of Orion. 
Scheat, the bright star in Aquarius. 
Schedar, in the breast of Cassiopeia. 
Sheat, in the thigh of Pegasus. 
Sirius, bright star in the great Dog. 
Virgin's spike, in the sheaf of Virgo. 
Yega, the bright star in the Harp. 
Zubenelg, in the north scale of Libra. 
Zubenesch, in the south scale of Libra 
6 



62 

PROBLEM I. 

To find the right ascension of the sun or a star. 

Rule — Bring the sun's place in the ecliptic* or the 
star, to the brass meridian, then the degrees of the 
equinoctial under the meridian, reckoning from Aries 
eastward, is the right ascension. 

1. What is the sun's right ascension on the 19th of 
April ? Ans. Twenty-seven and a half degrees. 

2. What is the sun's right ascension on the 1st Dec? 
Ans. Two hundred and forty-seven degrees fifty mi 

nates. 

3. What is the sun's right ascension on — 

Nov. 6th, May 7th, 

March 4th, August 10th, 

April 20th, Sept. 14th, 

June 16th, Oct. 23d, 

July 29th, Dec. 10th? 

4. What is the right ascension of Aldebaran ? 
Ans. Sixty-six degrees six minutes. 

5. What is the right ascension of — 
Alioth, Fomalhaut, Rastaben, 
Arcturus, Hyades, Rigel, 
Achernar, Menkar, Sirius, 
Bellatrix, Pleiades, Antares, 
Castor, Procyon, Pollux, 
Algol, Regulus, Acubens ? 

Note— The preceding stars, and their places in the constellations, 
may all be found in the preceding table. 

* By prob. 13. part 3. 



63 

PROBLEM II. 

To find the declination of the sun or a star. 

Rule — Bring the sun's place to the ecliptic,* or the 
Star to the brazen meridian, and the degree of the 
meridian over that place will be the declination. 

1. What is the declination of the sun, April 19th ? 
Ans. Eleven degrees, nineteen minutes north. 

2. What is the sun's declination, 

January 18th, April 12th, 

February 12th, May 23d, 

March 2d, June 2ist ? 

3. What is the declination of Aldebaran ? 
Ans. Sixteen degrees, six minutes. 

4. What is the declination of— 

Atair, Arcturus, Regulus, 

Algenib, Procyon, Kegel ? 



PROBLEM III. 

The latitude of the place, the day and hour bein^ 
given, to place the globe so as to represent the ap* 
pearance of the heavens at that time at the place ; 
and to point out the situation of the several stars. 

Rule — Elevate the pole for the latitude of the place; 
find the sun's place in the ecliptic, and bring it to the 
meridian, and set the index to 12 ; if the time be after- 
noon, turn the globe westward, if in the forenoon turn 
the globe eastward till the index points to the given 
hour. The surface of the globe then represents the 
appearance of the heavens at that place. 

1. Represent the appearance of the heavens for 
Jan. 13th, 4 o'clock A. M. and 8 o'clock P. M. 

* By prob. 13. part 3. 



61 

PROBLEM IV. 

To find the latitude or longitude of a given star. 

Rule — Screw the quadrant on the pole of the 
ecliptic, bring the star to the meridian, and the degrees 
of the quadrant between the ecliptic and star show the 
latitude, and degree of the ecliptic under the graduated 
edge of the quadrant is the longitude. 

1. What is the latitude and longitude of Arcturus ? 
Ans. Latitude thirty-one degrees north. Longitude 

two hundred and one degrees. 

2. What are the latitudes and longitudes of 

Fomalhaut, Cards Major, 

Canis Minor, Regulus ? 



PROBLEM V. 

The latitude or longitude of a heavenly body being 
given, to find its place on the globe. 

Rule — Fix the quadrant as in the last problem, and 
place it on the given degree of longitude in the eclip- 
tic ; then seek the given latitude on the quadrant, and 
under that degree is the place sought. 

1. What is the star whose longitude is two hundred 
and one degrees, and its latitude thirty-one degrees 
north ? 

Ans. Arcturus in Bootes. 

2. "What stars have the following longitudes and 
latitudes ? 

Longitudes. Latitudes. 

66i degrees, 5i degrees south, 

299 degrees, 29 degrees north, 

85 degrees, 16 degrees south. 



65 



ROBLEM VI. 

The right ascension and declination of a heavenly 
body being given, to find its place on the globe. 

Rule — Bring the given right ascension to the brass 
meridian, and under the given degree of declination 
on the meridian, is the place required. 

1. What is the star, whose declination is thirty 
degrees forty minutes south, and right ascension three 
hundred and forty-one degrees thirty-eight minutes 1 

Ans. Fomalhaut in the southern fish. 

2. What are the stars whose right ascensions and 
declinations are as follows : 

Right ascension. Declination. 

1838 M» 698 59' south, 

2778 32' 388 39' north. 
6* 



66 
QUESTIONS 

IN 

ASTRONOMY. 



What is astronomy ? 

What is the solar system ? 

What does astronomy teach ? 

What is a planet ? 

Of what is the solar system composed ? 

What is the diameter of each of the primary pla- 
nets ? 

What is the year of any planet ? 

What is tide ? 

What is an eclipse ? 

What is a great circle % 

What is the axis of a heavenly body ? 

What is an orbit ? 

What are the polar circles ? 

What is longitude on the earth ? 

What is a primary planet ? 

"VYliat is a secondary planet ? 

How does a planet perform its diurnal rotation ? 

What is declination ? 

What is a meridian ? 

What is a hemisphere ? 

When does an eclipse of the moon happen ? 

When does an eclipse of the sun happen ? 

How are the secondary planets distributed 1 

What is the distance of each of the primary planets 
from the sun ? 

In what time does each of the planets revolve round 
the sun ? 



67 

What is the rational horizon 
Describe the Ptolemaic and Tychonic systems. 
Describe the Copernican system. 
What is the number and names of the Asteroids ? 
Where are their orbits 'I 
What is diurnal rotation ? 
What is annual revolution 1 
What is an angle ? 

Describe the right, obtuse, and acute angles. 
What is a triangle ? 
What is the disc of a heavenly body ? 
What is a circle ? 
How are eclipses divided ? 
What is a digit ? 

Describe the diameter and radius of a circle. 
What is a map ? 
What is a globe ? 
What is the solar eclipse ? 
What is a lunar eclipse ? 
How is the tide caused ? 
How many hemispheres are there ? 
How are the tides divided ? 
What is flood tide ? And ebb tide ? 
What is a total eclipse ? 
What is a spring tide ? And neap tide ? 
What are the fixed stars ? 
Why are they supposed to be luminous bodies ? 
What is a constellation ? Their number ? 
What is the galaxy ? 

What is the nature of the planets and asteroids ? 
What is the sensible horizon ? 
How often do the spring and neap tides occur ? 
How often do the flood and ebb tides happen ? 
In what time does each of the primary planets re- 
volve on its axis ? 
How do the sun and moon differ in their attractions'* 
How do the planets revolve round the sun ? 



6S 



When is it new moon ? 

What are the celestial poles 

What are the poles of the earth \ 

When is it full moon ? . 

How are the circles of the spheres divided? 

Mention the principal great circles. 

What is a small circle ? 

What is harvest moon 1 

To what are small circles parallel f 

What is the diameter of the moon '? 

What is quadrature ? 

What is opposition ? 

What are parallels of latitude.- 

In what time does the moon revolve round the 

earth ? i ■) 

How many kinds of conjunctions are there i 
What are parallels of decimation 1 
Describe inferior and superior conjunction . 
What are parallels of latitude on the celestial globe* 
What is the moon's distance from the earth . 
What is centripetal force ? 
What is centrifugal force ? 
How is the earth known to be a spherical body / 
What are concentric circles ? j 

What is the occultation of a heavenly body * 

What are cardinal points ? 

How are the planets divided 1 

What is hail? 

How are the heavenly bodies divided/ 

What is the equator ? Has it any other names 

What are reckoned on it ? 

What is a luminous body 3 

What is an opaque body ? 

What is the hour circle 1 

Have the planets an atmosphere T 
What is wind 1 How is it caused ! 
What is the shape of the planets ? 



69 

What is air ? Is it a simple fluid 7 

What is the sun ? Its diameter ? 

What is the first meridian 7 

What is the brazen meridian 7 

How are the degrees numbered on it 7 

What does the sun afford to the other bodies 7 

What is the greatest longitude a place can have 7 

What is latitude 7 What is the greatest latitude 7 

What do some suppose the sun to be 7 

WTiat is the earth's hourly motion in its orbit 1 

What are fogs and mist 7 

How is longitude reckoned on the celestial globe 7 

What is latitude in the heavens 7 

What is the greatest latitude of the sun, a planet, 

or a star 7 

What is the greatest declination of the sun, a planet. 

or a star 7 

What is the velocity of light 7 
What is geocentric latitude and longitude 7 
What is heliocentric latitude and longitude 7 
How do you know the directions on a map 7 
What does the terrestrial globe represent ? 
What is right ascension 7 
What is oblique ascension 7 
What is the transit 7 
What is a climate 7 
What is the zenith 7 
j How many positions has the sphere 1 
Which planet is nearest the sun 1 
Which is the most distant from the sun ? 
What are comets ? And how distinguished 7 
How many primary planets are there 1 
When is Venus the evening star ? 
When the morning star ? 
What is a right sphere ? How represented 1 
What is the longest day and night at the poles 1 
What is an oblique sphere ? How represented 7 



70 

Which is the largest planet 7 

Which is the smallest 7 

What is a parallel sphere 7 

What is said of the day and night when the sun is 
in the solstitial points 7 

What is the ecliptic 7 Of what is it the path 7 

What is the equinoctial colure 7 

AVhat are the antipodes 7 

How is the heat of any planet increased or dimin- 
ished? 

What is snow 7 What is hail 7 

What are the equinoctial points ? 

How is the ecliptic divided 7 

Where does the most rain fall 7 and why 7 

Mention the names of the twelve signs, and the day 
on which the sun enters them. 

What are clouds 7 What are vapours 7 

When is the sun in the equinoctial points 7 

What is the solstitial colure 7 

When is the sun in the solstitial points 7 

How does a map differ from a globe 7 

In viewing the representations on the globe, where 
is the eye supposed to be placed 7 

What are the poles of the horizon 7 

Describe the variable winds. W^here do they pre- 
vail? 

What is the wooden horizon 7 

What is a vertical or azimuth circle 

What is the azimuth of a heavenly body 7 

Why do the superior planets never have inferior 
conjunction 7 

How do you find the latitude of any given 
place 7 

What is the latitude of Newfoundland ? 

How do you find the longitude of a given 
place 7 

What is a prime vertical ? 



71 

How do you find all the places in the latitude and 
ongitude of any given place 1 

What is a zone ? 

How many zones are there ? 

How wide are the frigid zones ? 

How do you find the antoeci of any place 1 

What is the diurnal arch ? 

How wide are the temperate zones 7 

How wide is the torrid zone ? 

How do you find the antipodes ? 

How do you find the perioeci of any place ? 

Describe the north and south frigid zones. 

What is the zenith distance ? 

What countries are in the north temperate zone 1 

What are the polar circles ? 

What are the tropics ? 

What countries are in the south temperate zone? 

What places are in the torrid zone ? 

How do you find the latitude and longitude of a 
given star ? 

How do you find the right ascension of the sun or 
of a star ? 

What is twilight ? 

What is the polar distance ? 

When does a place have a vertical sun ? 

When the day and hour are given at anyplace, how 
do you find what o'clock it is at any other place ? 

What is the nocturnal arch 1 

What places have a vertical sun ? 

Through what points do the tropics pass ? 

When is it the longest day in the southern he- 
misphere ? 

When is it the longest day in the northern n«„- 
misphere ? 

What causes the succession of day and night 1 

Why does the moon rise an hour later on each suc- 
cessive evening 1 



72 

What is reflected light ? 
What is the cause of twilight 7 

For questions adapted to practice upon the glob* s, 
he student is referred to the examples under the 
problems. 



ins end. 



■■■■-.'.,. ■ • 



No. 411 BROADWAY, NEW YORK. 

A;i Oral . 

I 

i i 

L ■■■- l 
sous, by Miss ! Kol 



do. 
do. 
do. 

do. 



do. by 
< [ to 

by 
story, by 

Baldwin's Primary Arithmetic. 
DuruPs French Grammar. 
Clarke's Elements of Astronomy. 
. Cent Toys. 
•it's Schoolmaster's Friend. 
I's Class Book of Natural History, I2mo, 
Geography and Atlas. 
! ect Remains, 32mo. extra cloth. 
uric, now edition. 
Rice I 

School Diary. 
Smart's Cicero, 12mo. 
Smith's Practical and Mental Arithmetic, be 
Traveler's Tour through the T . ni'.ecf State 

esting Game. 
Traveler's Tour through Europe. 
Towndrow's National Penman, Nog. 6 &, 
Valpy's Greek Grammar. 



Edit, 
nter- 



